The present invention relates to an implantable prosthesis and, more particularly, to a prosthesis for use in soft tissue repair and reconstruction.
Various prosthetic materials have been proposed to repair and reinforce anatomical defects, such as tissue and muscle wall hernias. For example, an inguinal hernia is commonly repaired using a sheet of biocompatible fabric, such as a knitted polypropylene mesh (BARD MESH). The fabric is typically sutured, stapled or otherwise provisionally anchored in place over, under or within the defect. Tissue integration with the fabric, such as by tissue ingrowth into and/or along the fabric, eventually completes the repair.
The attachment of the fabric to host tissue adjacent the defect can result in tension at the anchoring locations between the fabric and the tissue when abdominal pressure at the repair site is applied to the fabric, such as when an individual stands or strains, coughs, sneezes and the like. Tension at the anchoring locations may lead to postoperative pain for the patient, a recurrence of the defect, or the formation of a new defect. For example, a recurrence of the original defect or the creation of a new defect may result from failure of the suture line or other fastener, or tearing of the tissue due to tension at one or more of the anchoring locations. Tension on the suture line at the anchoring locations may also lead to ischemia of the tissue, resulting in enlargement of the suture holes and an eventual defect.
Scar formation (scarification) associated with the repair of tissue and wall defects may cause tissue shrinkage at the repair site, thereby contracting the repair fabric that has been integrated with tissue. Contraction of the fabric may cause patient discomfort as the fabric strains against the host tissue at the anchoring locations. Contraction of the fabric may cause failure of the fasteners and/or tearing of the tissue, in either case potentially leading to a recurrence of the defect, due to the fabric being pulled away from the tissue or muscle at the anchoring locations.
It is an object of the present invention to provide an improved method and a prosthesis for the repair of tissue or muscle wall defects.
The present invention is an implantable prosthesis and a method of repairing an anatomical defect, such as a tissue or muscle wall defect. The prosthesis is configured to reduce the likelihood that an applied force, such as due to intraabdominal pressure or tissue shrinkage, at the repair site can lead to detrimental effects associated with tension at the anchoring locations of the prosthesis and host tissue and/or contraction of the prosthesis. The prosthesis may reduce postoperative pain, and reduce the likelihood of either a recurrence of the defect or the creation of a new defect associated with tension and/or prosthetic contraction.
The prosthesis is particularly indicated for use in a repair in which tension and/or contraction are of potential concern. For techniques that employ fasteners, such as sutures, staples, adhesives and the like, to secure the prosthesis to the host tissue, the prosthesis may limit tension at the anchoring locations between the prosthesis and the host tissue. For fastener-less techniques, use of the prosthesis may be beneficial by limiting tension at the locations where tissue integrates with the prosthesis and/or by accommodating prosthetic contraction associated with shrinkage of tissue that has grown into and/or adhered to the prosthesis. The locations where fasteners join the prosthesis to host tissue and/or where tissue integrates with the prosthesis to secure the implant in place may all be referred to as xe2x80x9canchoring locationsxe2x80x9d.
The prosthesis may include a patch formed of a biologically compatible, flexible implantable repair fabric suitable for reinforcing tissue and closing tissue or muscle wall defects. The repair fabric may include a body portion for covering at least a portion of the tissue or muscle wall defect and an anchoring portion for securing, with or without fasteners, the fabric to host tissue, including tissue, muscle or the like, adjacent the defect. The repair fabric may have a plurality of interstices that are constructed and arranged to allow tissue ingrowth. The prosthesis may also include a plug that is employed in combination with the patch and is configured to be placed within the defect.
In one embodiment of the invention, the repair fabric may include a preformed region configured to reduce the prospects that an applied force at the repair site will cause detrimental tension at the anchoring location and/or to compensate for contraction of the prosthesis that may occur as a result of tissue shrinkage at the repair site during scarification.
According to one aspect of the invention, the preformed region has a predetermined amount of laxity that is greater than an amount of laxity at an anchoring portion of the fabric to reduce the prospects that an applied force at the repair site will cause detrimental tension at the anchoring location. According to another aspect of the invention, the preformed region has a predetermined amount of compensation to compensate for contraction of the prosthesis. According to a further aspect of the invention, the preformed region is configured to both reduce detrimental tension at the anchoring portion and to compensate for prosthetic contraction.
In another embodiment of the invention, the implantable prosthesis may include a body portion having a preformed three-dimensional shape and a cavity with an open end that is configured to be disposed over the defect.
In a further embodiment of the invention, the implantable prosthesis may include a plurality of preformed indicia on the anchoring portion that correspond to predetermined anchoring locations between the prosthesis and the tissue or muscle.
The prosthesis is particularly suited for repairing a tissue or muscle wall hernia located in one or more of the inguinal region, the inguinofemoral region and the femoral region. The prosthesis may include a medial section and a lateral section that are configured to be positioned adjacent the medial corner and the lateral end of the inguinal canal, respectively, when the prosthesis is placed in the inguinal canal. The prosthesis may include an extension that is configured to extend into the femoral region and cover the femoral ring.
Other objects and features of the present invention will become apparent from the following detailed description when taken in connection with the accompanying drawings. It is to be understood that the drawings are designed for the purpose of illustration only and are not intended as a definition of the limits of the invention.